


Tick Tock

by Provocatrixxx



Category: Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: BAMF John, Bombs, Ending Fix, Episode: s03e01 The Empty Hearse, Explosions, Fix It Fic, Gen, Minor Character Death, Non-Linear Narrative, Season/Series 03 Spoilers, The Empty Hearse Spoilers
Language: English
Status: Completed
Published: 2014-01-08
Updated: 2014-01-08
Packaged: 2018-01-08 01:33:26
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,294
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1126833
Author URL: https://archiveofourown.org/users/Provocatrixxx/pseuds/Provocatrixxx
Summary: <blockquote class="userstuff">
              <p>
  <i>"Demolition Charges," he says on a heavy out-breath, taking in the packets of C4 pushed into cracks in the brickwork. They’re wired together in a daisy-chain, and John traces the spirals with his torch-beam, following the wires up and up and up. They’re standing under Westminster now, beneath the Houses of Parliament themselves. The explosion, if it happens, is going to fell buildings for miles all around.</i>
</p><p> </p><p>I re-wrote the Tube Carriage scene to take John's Afghanistan tours into account. I also modified the bomb to take reality into account. And I added some context, for fun. And sadness, for impact. And confusion, because I can.</p>
            </blockquote>





	Tick Tock

**Author's Note:**

> With thanks to roane for constant encouragement, and for talking me down from deleting the whole thing at stupid o'clock in the morning.

**Camp Bastion, Helmand Province, Afghanistan  
1343hrs; 28 SEPTEMBER 2010**

The cheap white patio chairs are incongruous against the heavy canvas of the tents, bent out of shape and wobbly from the weight of boots and rifles and body armour. John’s pretty sure his sinks down into the sand a few inches as he settles into it, but it’s good to be out of the sun.

“Beer?”

“Where the hell did you find that?” John asks, accepting the warm can with a grin.

Felix sits down across from him, stripped down to t-shirt and combat trousers, his hair bleached blonde by the sun.

“Never you mind,” he says, tapping his nose, and John leans back in his chair and laughs. Ordnance Disposal Officers get all perks.

The beer is cheap and flat, warm from sitting inside the tent, but he drinks it down slowly, savouring the taste of England and a time before his world was reduced to bullets and sand and other people’s blood.

“When are you headed back out?” Felix asks, and John opens his eyes again, resettling his weight so as not to put too much strain on the chair.

“On the fourth. There’s a platoon of Lancasters heading out to Lashkar Gah.” It’s not done to smile about walking back into the red zone, but something in John’s face must give away how desperate he is to get back into the heart of the action, because Felix grins at him and kicks the leg of his chair.

“You’re wasted in the Medical Corps,” he says, “Come and see what real men do for kicks.”

“No thanks,” John says, “I’m going home in a plane, not a box.”

“I’ll drink to that.” Felix tilts his own can in a mockery of a salute, and John drains the last dregs of his warm beer. “These guys are amateurs. More own goals than the IRA, that’s for sure.” Felix laughs, but the sound is bitter, and John keeps his mouth shut, letting him talk.

“They try to make them technical, you see? Too many electronics. Timers. Remote controls. It’s the simple devices you want to watch out for. The tilt-switch in a football. The pressure-plate in a doorway. The more simple they are, the more people you’ll kill with them.”

John crushes the empty can between his fingers, sliding his hand over the comforting weight of his rifle.

***

**Westminster Tube Station**  
2134hrs; 05 NOVEMBER 2014

"There's a bomb, then? The tube carriage is carrying a bomb." Their feet are loud in the tiled passageway, and John feels his stride lengthening to keep up, shoulders squaring off as he hurries along behind Sherlock. There’s a bounce in Sherlock’s step now, and John can feel matching excitement humming in his own blood.

“Must be,” Sherlock says, and the happiness in his tone ought to be more disturbing.

“Right.” He still has Lestrade on speed dial, even after all these months. Contacting him will be faster than getting past the switchboard, especially on fireworks night. He draws his phone out, runs his thumb across the home screen.

"What are you doing?"

"I'm calling the police."

"What? No!" Sherlock glares at him, and John feels his resolve slipping, thumb pressing the button to locking the screen again even before his brain gives full permission. It seems he’s still hardwired for adventure, even after two long years.

"Sherlock,” he tries again, settling into his officer voice and forcibly pushing his shoulders square. “This isn't a game. We need to evacuate Parliament."

"They'll get in the way, they always do.” He waves his hand, and John slides his phone back into his pocket, glancing up and down the corridor as Sherlock slips the lock on the storage cupboard. “This is cleaner, more efficient."

"And illegal."

"A bit." The lock springs open with an audible snap, and John checks their tail one last time before following Sherlock into the dark.

***

**23, Ennismore Mews, Knightsbridge**  
1623hrs; 18th October 2014

“I’ve started. Dreaming. Again.” John looks down into his mug of tea as he admits it, swirls the last few mouthfuls in the bottom of the mug so they catch the last of the autumn sunlight. “Nice dreams, I mean. Not nightmares.”

“That’s good, John.” Ella smiles, and John finds himself smiling back at her. He still feels like every admission is sandpaper scrubbing across his skin, but it’s easier now. He is calmer. He has Mary to go back to.

“Do you want to tell me about them?” Ella asks.

She does this when she’s pleased, John’s learnt. Gives him options rather than commands. It means he’s healing, apparently. Means Ella has moved on from trying to draw his problems out and is working on his day to day normality.

“They’re just dreams, you know? Memories. People mostly. Conversation. That sort of thing.” He waves a hand vaguely, ducking his head away from her encouraging smile, the way she thumbs the spiral-binding on her notebook. He doesn’t tell her that he still dreams about the desert, about heavy weaponry and cold showers and brews passed around a fire pit. He doesn’t mention how much of a comfort it is to have his friends back, even if they’re only in his head.

“That’s good, John,” she says, “That’s very good.”

***

**Sumatra Road Tube Station**  
2140hrs; 05 NOVEMBER 2014

There’s a breeze blowing through the ventilation shaft, and John is grateful for his coat as they pick their way through the shadows, following the beam from Sherlock’s torch. John sweeps his own beam left and right, slower and more cautious, trying to map out the space in his head, counting the turns.

"I don't understand." Sherlock comes to a halt as the passageway widens out into an empty platform. Sumatra Road is dusty and half-finished, lacking the comfortable clinicality of Westminster and the District Line above them.

"Well that's a first.” John wanders further along the concrete, sweeping the walls with the beam of his torch. There’s no sign of damage to the tiling, and the platform is short and square, just the one exit up a flight of stairs, metal gates chained shut.

"There's nowhere else it could be." 

John is forced to concur. The stations stands empty and echoing, tracks humming with electricity, but perfectly bare.

"Oh!" Sherlock shouts, and John spins on his heel, catching the tail of Sherlock’s coat in the beam as Sherlock takes off running, leaping off the platform and down onto the train-tracks.

"What? Hang on, Sherlock!"

"What?" 

"That's,” John looks down at the track. He can hear the electricity humming through the metal, deafening in the darkness that surrounds them. “Isn't it? Live?"

"Perfectly safe as long as we avoid touching the rails,” Sherlock says, as though it’s the simplest thing in the world.

"Of course, yeah. Avoid the rails. Great." John jumps, flashing the beam of his torch around his feet and mentally grasping hold of the space.

"This way,” Sherlock shouts, and takes off into the tunnel.

***

**Church of St Mary & St John, Hawes, Yorkshire**  
1057hrs; 9th August 2011

None of them are wearing coats. The rain falls down around them, cold and indifferent, and the soil that slowly covers Felix’s coffin goes on heavy and bitter. John hunches his shoulders a little more, counts the scratches on the toes of his shoes as clod after clod of earth hits the lid of the walnut box. 

They have no reason to linger, but still none of them move, five of them in a loose ring, doing one last sentry duty for their departed friend. Louisa, pale and trembling in her grief, had already been borne away by fluttering, concerned-sounding relatives. She’d muttered something about a wake at the house, wine and nibbles and soft-spoken people. John presses his toe into the grass and watches the water bubble up through the sodden soil. Felix’s old Army friends are too loud and ugly for a quiet party in the big empty house on the hill.

“One last drink to see the old boy off?”

John’s not sure which of them speaks, but he finds himself crunching down the gravel with them anyway, five sodden ex-soldiers falling into step from habit. He tucks his cane into his side and concentrates on straightening his back, the damp suit-jacket clinging to his shoulder-blades as he moves.

There’s only one pub in the village, the walls faced in sandstone and soaked in beer. They order bitters, in honour of Felix, and form a loose circle around the far end of the bar, out of sight of prying eyes.

“To Felix, who finally ran out of lives.”

“Felix.” They raise their glasses, and down the pints without meeting each other’s eyes.

***

**Sumatra Road Tube Station**  
2152hrs; 05 NOVEMBER 2014

"Ha, look at that." Sherlock stops abruptly, and John almost misses it in the near darkness. He can hear his own pulse in his ears now, competing with the electric buzz for his attention. "John?"

"Mm?" They are deep under London now, and the darkness is thick and slightly worrying. John traces the walls with the beam of his torch, mindful of his feet as he turns. There’s a ventilation shaft above them, and John walks forwards a few paces, following the ceiling as it climbs in a wide circle.

"Demolition Charges," he says on a heavy out-breath, taking in the packets of C4 pushed into cracks in the brickwork. They’re wired together in a daisy-chain, and John traces the spirals with his torch-beam, following the wires up and up and up. They’re standing under Westminster now, beneath the Houses of Parliament themselves. The explosion, if it happens, is going to fell buildings for miles all around.

Behind him, Sherlock walks further down the train track, slower now, the light from his torch swinging from side to side as he goes. The tube car is resting about twenty metres away from the shaft, partially hidden by a slight bend in the rails. John moves towards it cautiously, following the line of the wires pinned to the wall. The bundles are kept neat with cable-ties, and John swallows at the neatness and simplicity of it all.

“Wait, Sherlock,” he says, and his voice comes out commanding enough for Sherlock to stop and wait for him to catch up. “They’re clever. Neat about their work. There could be anything in that car.”

“Let’s not stand around chatting about it then,” Sherlock says, but he lets John move forwards first, and waits while he sweeps under the carriage for anything obvious. There’s nothing, no sign of a disturbance in the metal frame, no pressure plate waiting to take the weight of them.

“Do you think it’s booby-trapped?” John asks.

“No.” Sherlock’s grin is leant a slither of violence but the low light, and John feels an involuntary shiver run down his spine. “They’re too arrogant for that. They’ve taken too many precautions. Who could possibly find a tube car in a station that doesn’t exist?”

John holds his breath as Sherlock pushes down on the handle, but the door swings open easily, and the quick rush of pressure and then fire never comes. He grins again when he spots John’s face, swinging himself up into the car in a single bound. John follows more slowly.

“It’s empty,” he says, looking around, “there’s nothing.”

"Isn't there?" Sherlock crouches in the gangway, curling his fingers around one of the cushions and tugging until it comes away. "This is the bomb."

"What?" John leans over to get a better look, and the neat bundle of wires disappearing into a block of C4 make his stomach drop. He counts the seats, calculates the pounds. The carriage alone could take out half the Tube network.

"It's not carrying explosives. The whole compartment is the bomb."

Sherlock’s eyes are wide, and his breathing is fast and heavy in the enclosed space. He stands again, kicking at a loose section of the flooring. John almost doesn’t want to look when Sherlock kneels down again, lifting the plastic board up to reveal the time and power unit for the whole device.

"We need bomb disposal." Even from where he’s standing, John can see the deceptive simplicity of the device, the wires soldered neatly into a box, a digital clock-face wired to the top. 

"There may not be time for that now," Sherlock says quietly, and all traces of his earlier excitement are gone.

"So what do we do?"

"I've no idea."

“Right.” John kneels down gingerly on the compartment floor, resting his weight on one hand and shining the torch around the mechanism. The wires are pulled together in three twisted ropes, coiled neatly and soldered into to two slim wires that feed into the metal box.

“What are you doing?” Sherlock asks, but John just shakes his head, closing his eyes for a moment as he tries to guess what’s inside the box. It’s just larger than a match-box, and only loosely held in place on top of the coils of wire.

“It’s a tilt switch,” he says eventually. “Mercury, probably. If we touch it, or jostle the carriage, it’s going to detonate the bomb.”

“Oh,” Sherlock says, rocking back onto his heels and pressing his hands together underneath his chin. “Oh!”

The lights in the carriage flicker to life, and John feels his heart leap within his rib-cage, a white shock of fear running through him like a wave. The little clock face lights its digits, a shiny red 03:00 gently ticking down the seconds. 

"My God! Why didn't you call the police!?" He hisses, leaning back from the bomb to scrub his hands across his face.

"Can you just-"

"Why do you never call the police?"

"Well, it's no use now,” Sherlock protests, but in the brightness of the carriage lights, his face is deathly pale. “You should go, John.”

“What!?” John glances behind himself briefly, trying to work out if it’s a trick. Something Sherlock set up to frighten him again. But there’s nothing, and the bomb between his knees is frighteningly real, the C4 packed into the chairs all around them all too capable of ripping half of London to shreds.

“Go,” Sherlock says again, and he’s so pale and urgent that John can’t imagine a trap.

“There’s no point now, Sherlock,” John tells him, and as watches the digits tick down, it hits him how real this is. “If we don’t do this now, other people will die.” He refuses to think any further about what that means.

***

**102, Bell Street, Marylebone, London**  
0427hrs; 16th October 2014

The thing no-one tells them is just how green and beautiful Afghanistan is. John finds himself strapped tight into a centre seat in a puma, legs dangling as the pilot banks sharply, and through the open doors, all John can see is lush green grass.

The Puma drops him and six members of three section down near the city of Qalat, and they take cover for half an hour in the long grass. John runs his fingers through the soft leaves, turning them over in his hand and admiring their greenness. It’s a whole different country when you have the luxury of looking through your eyes and not a rifle sight.

Captain Jamie claps him on the shoulder, and John follows the section down a dirt track towards a temporary aid station set up right on the outskirts of the town.

“We’ll be here for about a week,” the Captain tells him. John looks out at the countryside around him and smiles.

The green fades out to grey and then to blue, and John slowly becomes aware of his bedroom, the softness of the duvet, the warm fingers running absently over his chest.

“Mm?” he says, shaking himself out of the dream, “Sorry, did I wake you?”

“Maybe a little bit,” Mary admits, but she smiles and cuddles into his side. “What were you dreaming about?”

“Afghanistan,” he says, and feels her stiffen a little against him. He slides his arm around her shoulders, pulls her in tight and breathes in the the soft, clean smell of her hair. “Good dreams,” he promises. He feels her nod, her body warm and soft against his, and he counts her breaths as she eases back to sleep.

He didn’t dream until she came along. Perhaps he dreams now because she makes him feel safe.

***

**Sumatra Road Tube Station**  
2157hrs; 05 NOVEMBER 2014

“Maybe,” John says, and Sherlock looks at him expectantly, as though he believes John can solve it, “maybe we should detonate it ourselves. Just. Cut the wires. It would still blow the main charge, but-”

“Why?” Sherlock asks, frowning at John as though he’s gone mad.

“Because then it’s only us who’ll die. Potentially.”

“Potentially.”

“Yes. Potentially! I’m not an ATO Sherlock! I don’t know how to fix this!” The sound of his voice reverberates about the carriage, and John forces himself to stop talking. “Do you have a better idea?” he asks, more quietly, and all the while, the little red digits click on towards zero.

“Why is there a timer?” Sherlock asks.

John looks down again, watches the numbers tick over, five seconds of precious time gone already. His hands twitch for a radio, a rifle, but there’s nothing but the torch.

“I don’t know,” he says, closing his eyes and picturing the wires inside the box again. Mercury tilt-switches are the most common, a blob of liquid metal at the bottom of a glass tube, the whole thing on a pivot, completing the circuit when nudged or jostled. It only takes a tremor. The slightest move. Complete the circuit. Blow the charges. John shudders.

“Well, think!” Sherlock’s hands are clasped behind his back, but he’s not pacing, and John is grateful for that.

Settling more comfortably on his knees, John breathes in slowly, ignoring the numbers ticking away inches beneath his fingertips.

“Something has to jostle the train,” he says, “the timer makes the circuit live, but it’s not complete until the tilt switch is activated. They’re going to-”

“They’re going to drive the train!” Sherlock says, faster, and John opens his eyes to meet Sherlock’s bright ones, excitement clear on his face. “There’s a bend in the track just before the ventilation shaft! Would that be enough to tilt the switch?”

“Yes!”

“How long do we have, John?”

“Two minutes and twenty seconds, nineteen, eighteen,” John says, climbing to his feet carefully, mindful of the bomb-makers and their propensity for own goals. 

“We have to dismantle the mechanism that lets them drive the train remotely.” He starts to turn away, but John grabs him by the lapels, holds him still.

“Slowly,” he commands, “I don’t know how sensitive the tilt switch is.” Every step could be their death-sentence, and John holds tight to the thick wool of the coat until he is sure that Sherlock understands.

When he lets go, Sherlock nods and creeps off towards the head of the train. John pulls up the timer on his watch, waits for the digits to tick down to two minutes and sets the stopwatch. It sends a chill down his spine, his own personal death clock, and he moves to the front of the carriage as quickly as he dares.

“How are you going to dismantle it?” he asks when he catches up.

“No idea. Isn’t it exciting?” But Sherlock’s voice is pitched just a touch too high, and the smile on his face is more of a grimace.

The doors to the driver’s cab slide open easily, and Sherlock walks up to the console, his palms pressed together under his chin. There’s a bank of buttons and switches, none of them labeled, and John has no idea where to even start.

“You don’t know what the buttons are, do you?” he asks quietly.

“It’s not about the buttons,” Sherlock tells him, and John lets him have his silence, taking in the set-up. The cab itself looks relatively undisturbed, the web of wires kept away from the console. 

“It’s the box,” Sherlock says, pointing, and John follows his finger to the corner of the cab where there’s a black metal box propped against the window,, two wires feeding out of it and down into the console. “It’s a radio amplifier. It boost the signal just enough,” Sherlock says, reaching towards the box, “for someone to control the train remotely.”

He pulls the wire, and John closes his eyes against the inevitable explosion. But nothing comes.

“OK,” John says slowly, willing his pulse to calm down enough for him to think. “OK, they can’t control the train now. And if the train doesn’t move, the switch can’t tilt, and the bomb won’t detonate.”

“Unless there’s a backup.”

“Unless there’s a secondary.” He agrees and opens his eyes again. One minute now, 59 seconds, 58. “They wouldn’t risk a secondary,” John decides. “The bomb’s too simple. It’s too clever. You don’t want to get too technical. Too many electrics. Timers. Remote controls. It’s the simple ones that kill you.”

49 seconds. 48. 47.

Sherlock watches John’s face rather than the numbers. He can feel Sherlock’s gaze on him and the intensity of it is breathtaking.

"I wanted you not to be dead," he says, because it’s the truth and the silence is suffocating him.

"Yeah, well. Be careful what you wish for."

John looks up, watches the shadows slide across Sherlock’s face as he tilts his head, still looking at John. His face is sharper now, and he looks tired in a bone-deep way that is so different from his usual disaffected boredom. 

“Look, I’m not good at,” John waves his left hand between them, “this sort of thing. But.” He stops again, because they have thirty seconds now, and these words have to be the right ones. “I’m glad you came back,” he says. And Sherlock’s face goes blank.

26 seconds, 25, 24. John is tempted to count them out loud, anything to fill the silence between them, to give him an excuse to look away from Sherlock’s too-bright eyes and unreadable face.

“Forgive me!” Sherlock says, fast and desperate, and John wants to reach out, pin them in these last few seconds, touch Sherlock’s face and reassure himself that everything was real. That Sherlock came back from the dead for him.

“Of course I forgive you,” he says instead, and Sherlock closes his eyes and turns his head away.

19 seconds. 18. 17. John glances back at the time and power unit, the little red digits flashing, reflected by the wires.

“John-” Sherlock starts, but John holds out his hand, and Sherlock swallows the rest of his sentence.

13 seconds. 12. 11. 

He ought to think of Mary, ought to picture her face, the future they’re going to have together. He doesn’t. His pulse speeds and thumps in his ears, turning into the desperate whirr of helicopter blades, and John closes his eyes against the invading blue skies, feels himself mouth ‘please God, let me live.’

“Sherlock!?” 

John forces his eyes open, feels his hand curl tight around the doorframe as he tries to make sense of the commotion in the tunnel.

“Stop!” he shouts, as loud as he can. “Stand still. Don’t touch the train.”

***

**Sumatra Road Tube Station**  
2203 hrs; 05 NOVEMBER 2014

“Did you get a look at the switch?” Major Brown asks him, his keen eyes focused on John even as Sergeant Knowles straps the bomb suit onto him.

“The TPU’s sealed up. I didn’t dare touch it, I’m afraid. It looked about the right size though.” John holds up his hands as he speaks, demonstrating the size of the detonator.

Major Brown beams at him, and John doesn’t quite know what to make of it.

“Excellent!” he says, and then turns away.

Lestrade claps John on the shoulder, slowly drawing him away, back down the tunnel towards the platform. They pass the rest of the Ordinance Disposal Unit, carefully studying the charges set into the walls.

“Has Parliament been?” John asks, waving his hand towards the ceiling because his throat is too dry to form the words properly.

“We’re working on it,” Lestrade tells him, in the soothing tone he uses when they’re not quite out of the woods yet. “How close was it?” he asks quietly, and John realises that Lestrade’s hand is still on his shoulder.

“I don’t think I want to know.” He says, and is grateful when Lestrade squeezes his shoulder and then lets go.

***

**Hamidi Mena, Kandahar Province, Afghanistan**  
1209 hrs; 9th August 2011

He can feel the sweat dripping down the curve of his neck, sticky and prickly where it meets the end of his hair. He can block out the heat of the sun, the sound of curious local children chattering away just behind the cordon, watching the strange man in his heavy suit bending over their football. But he can’t block out the sweat that drips down his spine.

He cuts the football open one stitch at a time, counting his heartbeats, working in the pauses. The faintest tremor is enough to tilt the switch, to close the circuit and blow the charge. Another stitch. Another pause. The leather comes away painfully slowly.

And then, when the itch becomes too much, he tilts his head, shrugs his shoulders up an inch or so. The pliers snag on a stitch, the lightest touch, and the leather caves in. He has just enough time to smile at the stupidity of it all, to watch the liquid-silver mercury slide frictionless in its tiny glass prison, and then the world fades white around him.

Always, in the end, it’s the simple things that kill you.

THE END

**Author's Note:**

> I set it in the future because I am bad at maths and worse at dates.
> 
> I originally had date time groups for the dates, but then I remembered that even I don't understand them half the time, so including them would be stupid. The Afghan dates are in local time.
> 
> “Felix” was the callsign given to Ordnance Disposal officers over in Northern Ireland during the troubles. It was a mishearing of ‘phoenix’ over bad coms, but it stuck because of the story of the cat Felix and his nine lives.
> 
> His comment about the [Afghan bombers being ‘amateurs’](http://www.wired.com/dangerroom/2008/12/how-to-defeat-i/) is true.
> 
> C4 is short for Composition 4 and is a very stable explosive which is easily moulded and therefore perfect for squeezing into cracks. It will only detonate if a shock wave is passed through it.
> 
> A daisy chain is a chain of explosives which set each other off in a chain.
> 
> Afghanistan [really is beautiful](http://dpshots.com/travel-photography/afghanistan-pictures.html), especially near Qulat. 
> 
> Mercury tilt switches look [like this](http://sub.allaboutcircuits.com/images/54001.jpg). Once they are jostled and the blob of mercury hits the other end of the tube, it completes the circuit. I have given this bomb a tilt that was designed to be sensitive on only one axis (side to side) to make it more plausible for John and Sherlock to survive. Disabling the ability for the bomb makers to drive the train made the bomb ‘safe’, and the tilt was not so sensitive as to be tripped by John and Sherlock walking about in the car.
> 
> Also, I’m not a bomb-maker, I promise.


End file.
